On 12/6/2010 9:32 AM, jimlux wrote:
> n8de@thepoint.net wrote:
>> Might be a 'great' LUBE, but what about electrical/electronics use?
>> Dissimilar metals play havoc with some joints.
>>
>> Had a bad time with 'birdies' due to one dissimilar joint where I
>> had grounded a coax line at the base of a tower with copper strap
>> secured to the aluminum tower using Noalox. Seems the
>> copper/aluminum junction rectified every shortwave station that the
>> tri-band yagi heard!
>>
>
> I don't know that I'd use MoS2 on tower joints. It's more for high
> pressure mechanical moving things (e.g. drive chains on motorcycles).
> I think, because the Molybdenum is chemically bound to the sulfur,
> it's not going to react with the other metals and form dielectric
> junctions.
> MoS2 is also an insulator (like most sulfides), so I don't know that
> it would perform the function of a NoAlOx kind of material, which, in
> part, is designed to ensure that you have good conductivity all the time.
I'd not use any lube on tower joints, or any material that would reduce
the gripping action of the leg overlap as that would reduce the over all
tower strength and put more load on the bolts, which could lead to the
elongation of the bolt holes.
Also when use on bolt threads the torque required for a specific linear
pull on the bolt is reduced substantially. In compression on a tower
leg never-seez on the threads can lead a greatly increased crushing
force on the tower legs. That needs to be taken into account when used
on tower bolts.
73
Roger (K8RI)
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk